The presence of high levels of biogenic amines is detrimental to the quality and safety of fish sauce. This study investigated the effects of ethanol extracts of spices, including garlic, ginger, cinnamon, and star anise extracts, in reducing the accumulation of biogenic amines during fish sauce fermentation. The concentrations of biogenic amines, which include histamine, putrescine, tyramine, and spermidine, all increased during fish sauce fermentation. When compared with the samples without spices, the garlic and star anise extracts significantly reduced these increases. The greatest inhibitory effect was observed for the garlic ethanolic extracts. When compared with controls, the histamine, putrescine, tyramine, and spermidine contents and the overall biogenic amine levels of the garlic extract-treated samples were reduced by 30.49%, 17.65%, 26.03%, 37.20%, and 27.17%, respectively. The garlic, cinnamon, and star anise extracts showed significant inhibitory effects on aerobic bacteria counts. Furthermore, the garlic and star anise extracts showed antimicrobial activity against amine producers. These findings may be helpful for enhancing the safety of fish sauce.

Dynamics and diversity of microbial community succession of surimi during fermentation with Actinomucor elegans were analyzed by high‐throughput sequencing. The results showed that Cyanobacteria represented by Streptophyta were found to have the highest diversity at the beginning of fermentation and then decreased sharply with the fermentation proceeded. Then, Proteobacteria became the most dominant phylum followed by Firmicutes with a relative abundance of 77.77% after 48 h of fermentation. Actinobacteria and Bacteroidetes were occasionally present. Enterobacteriaceae, Moraxellaceae, Xanthomonadaceae, Bacillaceae and Enterococcaceae were found to account for almost all the diversity during fermentation. Stenotrophomonas, Acinetobacter and Enterococcus were three dominant genera that were classified with the relative abundance of 18.19, 19.76 and 7.74% after 36 h of fermentation, respectively. The bacterial diversity of surimi decreased after 48 h of fermentation as some species gradually became dominant and some were almost undetectable. In addition, from the results of traditional microbiological analysis, counts of mesophilic aerobic bacteria, total enterobacteria, enterococci and Pseudomonas all increased with the change in pH value of surimi, which decreased from 7.16 to 5.93 during fermentation.Practical ApplicationsData about dynamics and diversity of microbial community succession in surimi during fermentation will provide theoretical basis for controlling of pathogenic microorganisms, and ensuring the safety of the fermented surimi product.

Histamine is one of the most concerned safety indicators in fish sauce. Considering its charge property, electrodialysis (ED) was used to control the histamine in fish sauce, and studies were focused on three operating parameters: input current, pH, and flow velocity. A Box–Behnken design and response surface methodology was adopted to derive a statistical model, which indicated that 5.1 A input current, pH 3.8, and 40 L∙h−1 flow velocity were optimal operation conditions. Under this condition, the histamine removal rate reached 53.41% and the histamine content met the allowable histamine limit of below 400 mg·kg−1 in fish sauce, while the amino nitrogen (ANN) loss rate was only 15.46%. In addition, amino acids and volatile compounds changed differently during ED. As a result, with decreased histamine, the fish sauce after ED was also less salty and less fishy. The study first explored utilizing ED to remove histamine from fish sauce, which has positive implications for promoting the safety of aquatic products.